Would you be interested in an electric car that travels 300 miles on a single charge but its battery costs about 70 percent less than today's packs? It's something to look forward to in the next few years, says lithium-ion battery research company CalBattery . CalBattery has designed a new li-ion battery with a silicon-graphene anode promising a major improvement in battery energy density. The design is based on what the company calls its "GEN3" silicon-graphene composite anode material for li-ion batteries , the technology breakthrough for which was developed at Argonne National Labs. The company entered the li-ion battery cells into the Department of Energy's 2012 Start UP America's Next Top Energy Innovator challenge, and is a finalist in the competition. Independent test results show that CalBattery's cells have an energy density of 525 watt-hours per kilogram, and ano...